Modified ziegler-natta (pro) catalysts and system

ABSTRACT

A modified Ziegler-Natta procatalyst that is a product mixture of modifying an initial Ziegler-Natta procatalyst with a molecular (pro)catalyst, and optionally an activator, the modifying occurring before activating the modified Ziegler-Natta procatalyst with an activator and before contacting the modified Ziegler-Natta procatalyst with a polymerizable olefin. Also, a modified catalyst system prepared therefrom, methods of preparing the modified Ziegler-Natta procatalyst and the modified catalyst system, a method of polymerizing an olefin using the modified catalyst system, and a polyolefin product made thereby.

FIELD

The field includes procatalysts, olefin polymerization catalysts,methods of synthesis, methods of polymerizing an olefin, and polyolefinsmade thereby.

INTRODUCTION

Olefins may be polymerized in gas phase, slurry phase, or solution phasepolymerization processes comprising reactions catalyzed by molecularcatalysts or Ziegler-Natta catalysts. Molecular catalysts are preparedby contacting molecular procatalysts with an aluminoxane such as amethylaluminoxane or boron-based activator such as a(per)fluorophenylboron compound.

Ziegler-Natta catalysts are prepared by contacting Ziegler-Nattaprocatalysts comprising titanium halides on a magnesium chloride supportwith an alkylaluminum activator such as triethylaluminum (TEA),triisobutylaluminum (TIBA), diethylaluminum chloride (DEAC),diethylaluminum ethoxide (DEAE), or ethylaluminum dichloride (EADC).

U.S. Pat. No. 4,612,300 to W. M. Coleman, III, mentions a novel catalystfor producing relatively narrow molecular weight distribution olefinpolymers. Employs a Ziegler-Natta magnesium halide supported catalystcontaining both titanium and vanadium. Catalyst must contain asufficient quantity of hydrocarbylaluminum, aluminum halide, orcombination thereof.

WO 95/11264 A1 to T. E. Nowlin et al. (NOWLIN) mentions polyolefinblends of bimodal molecular weight distribution.

WO 96/12762 A1 to J. A. DeGroot et al. (DEGROOT) mentions polyolefincompositions exhibiting heat resistivity, low hexane-extractives andcontrolled modulus.

U.S. Pat. No. 6,723,677 B1 to J. V. Estrada et al. (ESTRADA) mentions ahigh activity Ziegler-Natta catalyst for high molecular weightpolyolefins. By controlling the holdup times, concentrations andtemperatures for mixing the components of aluminum, titanium andmagnesium based catalyst for solution polymerization it is possible toprepare a catalyst having a high activity, which prepares high molecularweight polyolefins. Generally, a catalyst loses activity and produceslower molecular weight polymer at higher temperatures. The catalystpermits comparable polymers to be produced with higher catalyst activityand at higher reaction temperatures by increasing the concentration ofthe components used during the preparation of the catalyst.

U.S. Pat. No. 7,592,286 B2 to G. Morini, et al. mentions a process forthe preparation of a catalyst component and components therefromobtained. Catalyst component comprises a Mg compound, a Ti compound andan electron donor compound (ED) selected from alcohol, glycols, esters,ketones, amines, amides, nitriles, alkoxysilanes and aliphatic ethers asessential compounds, comprising two or more steps of reaction involvingthe use of at least one of said essential compounds as fresh reactantalone or in a mixture in which it constitutes the main component, saidprocess being characterized by the fact that in the last of said one ormore reaction steps the essential compound used as a fresh reactant isthe ED compound.

US 2014/0088275 A1 to L. Richter-Lukesova et al mentions a process formanufacture of a mixed catalyst system for the copolymerization ofethylene with c1-C12 alpha-olefins.

U.S. Pat. No. 9,255,160 B2 to S. Desjardins, et al. mentionsmulti-metallic Ziegler-Natta procatalysts and catalysts preparedtherefrom for olefin polymerizations. Catalyst compositions comprisingthree or more transition metals increase catalyst efficiency, reducepolydispersity, and increase uniformity in molecular weight distributionwhen used in olefin, and particularly, linear low density polyethylene(LLDPE), polymerizations. Resulting polymers may be used to form filmsthat may exhibit improved optical and mechanical properties.

SUMMARY

A hybrid catalyst comprises a Ziegler-Natta catalyst and a supportedmolecular catalyst for use, at the same time, in a single reactor forgas phase and slurry phase polymerization processes to producepolyolefin compositions comprising a polyolefin macromolecules producedwith a molecular catalyst and polyolefin macromolecules produced with aZiegler-Natta catalyst. Others have found it necessary to support themolecular catalyst onto the Ziegler-Natta catalyst. This is becausemorphology control of catalyst particles is critical for gas phase andslurry phase polymerization processes in order to ensure processcontinuity. But such prior pre-formed hybrid catalysts have drawbacks.The relative contribution of the Ziegler-Natta catalyst and thesupported molecular catalyst for forming polyolefin macromoleculescannot be easily adjusted in the hybrid catalyst. Instead a differenthybrid catalyst must be synthesized for each polyolefin compositiontargeted. Also, prior processes of synthesizing hybrid catalysts arecomplicated and lengthy. A typical synthesis comprises activating anunsupported molecular procatalyst with methylaluminoxane to give anunsupported molecular catalyst, supporting at least some of theunsupported molecular catalyst onto a Ziegler-Natta catalyst particlesto give a hybrid catalyst, and removing any remaining unsupportedmolecular catalyst from the hybrid catalyst to give a hybrid catalystcomposed of a supported molecular catalyst on a Ziegler-Natta catalystand free of unsupported molecular catalyst. Ziegler-Natta catalysts usedto make such hybrid catalysts are mostly limited to silica-supportedZiegler-Natta catalysts.

We (the present inventors) realized that high temperature solutionpolymerization would be a more suitable process for using a molecularcatalyst and a Ziegler-Natta catalyst at the same time in the samereactor since the requirements on particle morphology control no longerexist. Solution phase polymerizations using a Ziegler-Natta procatalystand a molecular procatalyst can be further simplified if one could finda way to use only one catalyst feed comprising a premixture of theZiegler-Natta procatalyst and molecular (pro)catalyst that can preserveat least a portion of the catalytic activity of the molecular catalyst.The premixture may be used as a single procatalyst. The polyolefincomposition produced using the premixture may be composed of polyolefinmacromolecules that are different in structure or composition and mayhave improved properties than the polyolefin macromolecules andproperties produced by single catalysts.

We conceived a technical solution that provides a modified Ziegler-Nattaprocatalyst that is a product mixture of modifying an initialZiegler-Natta procatalyst with a molecular (pro)catalyst, and optionallyan activator, the modifying occurring before activating the modifiedZiegler-Natta procatalyst with an activator and before contacting themodified Ziegler-Natta procatalyst with a polymerizable olefin. Also, amodified catalyst system prepared therefrom, methods of preparing themodified Ziegler-Natta procatalyst and the modified catalyst system, amethod of polymerizing an olefin using the modified catalyst system, anda polyolefin product made thereby.

DETAILED DESCRIPTION

The Brief Summary and Abstract are incorporated here by reference.Examples of embodiments include the following numbered aspects.

Aspect 1. A method of polymerizing an olefin using a modified catalystsystem that comprises a product of reaction of a modified Ziegler-Nattaprocatalyst with an activator in (C) a saturated or aromatic hydrocarbonliquid, the method comprising contacting at least one polymerizableolefin in a reactor with the modified catalyst system under effectiveconditions to give a polyolefin product; wherein the modifiedZiegler-Natta procatalyst is prepared prior to the contacting step bymixing an initial Ziegler-Natta procatalyst and a molecular(pro)catalyst together in (C) a saturated or aromatic hydrocarbon liquidunder modifying conditions comprising a modifying temperature less than100° C. and a modifying time of at least 1 minute, and optionally anactivator, to give the modified Ziegler-Natta procatalyst. The modifiedZiegler-Natta procatalyst is different in at least one of composition,structure, activity, function than a mixture of the initial (unmodified)Ziegler-Natta catalyst and molecular (pro)catalyst, and, if present, theactivator.

Aspect 2. The method of aspect 1 (i) wherein the initial Ziegler-Nattaprocatalyst is (B) a magnesium halide-supported titanium procatalyst;wherein the (B) magnesium halide-supported titanium procatalyst has beenprepared by contacting (D) a solid particulate consisting essentially ofmagnesium halide with (E) titanium tetrachloride in the (C) saturated oraromatic hydrocarbon liquid so as to give the (B) magnesiumhalide-supported titanium procatalyst; (ii) wherein the molecular(pro)catalyst consists essentially of a molecular ligand-metal complex(pro)catalyst; or (iii) both (i) and (ii). The (C) saturated or aromatichydrocarbon liquid in which (B) is prepared may be the same (C)saturated or aromatic hydrocarbon liquid in which the modifiedZiegler-Natta procatalyst is prepared (e.g., one-pot preparations) andthe same (C) saturated or aromatic hydrocarbon liquid in which themodified catalyst system is prepared.

Aspect 3. The method of aspect 1 or 2 wherein the modifying conditionscomprise: (i) a modifying temperature from 0° C. to 50° C.; (ii) amodifying time from 2 hours to 3 months; (iii) an inert gas atmosphere(e.g., N₂, helium, argon, or a mixture of any two or more thereof); (iv)both (i) and (ii); (v) both (i) and (iii); (vi) both (ii) and (iii); or(vii) each of (i), (ii), and (iii).

Aspect 4. The method of aspect 1 or 2 or 3 wherein the modified catalystsystem further comprises (G) an organoborate or (H) an organoboron.

Aspect 5. The method of any one of aspects 1 to 4 wherein: (i) the atleast one polymerizable olefin is ethylene and the polyolefin productcomprises a polyethylene; (ii) the at least one polymerizable olefin isat least one (C₃-C₄₀)alpha-olefin and the polyolefin product comprises apoly((C₃-C₄₀)alpha-olefin); or (iii) the at least one polymerizableolefin is a combination of ethylene and at least one(C₃-C₄₀)alpha-olefin and the polyolefin product comprises apoly(ethylene-co-(C₃-C₄₀)alpha-olefin) copolymer.

Aspect 6. The method of any one of aspects 1 to 5 wherein: (i) theinitial magnesium halide-supported titanium procatalyst is free of Al(molar ratio Al/Mg=0); (ii) the initial magnesium halide-supportedtitanium procatalyst is characterized by a molar ratio of Al/Mg from >0to <0.05; (iii) the magnesium halide of the initial magnesiumhalide-supported titanium procatalyst is magnesium chloride; (iv) themagnesium halide of the initial magnesium halide-supported titaniumprocatalyst is magnesium bromide; (v) both (i) and (iii); (vi) both (i)and (iv); (vii) both (ii) and (iii); (viii) both (ii) and (iv).

Aspect 7. The method of any one of aspects 1 to 6 wherein: (i) the (D)solid particulate consisting essentially of magnesium halide has aBrunauer, Emmett, Teller (BET) surface area of ≥200 square meters pergram (m²/g) as measured by BET Surface Area Method, described late; or(ii) the (D) solid particulate consisting essentially of magnesiumhalide has been prepared by contacting a solution of (F) adialkylmagnesium compound dissolved in the (C) saturated or aromatichydrocarbon liquid with 1.95 to 2.05 mole equivalents of hydrogen halideto give a suspension of the (D) solid particulate consisting essentiallyof magnesium halide in the (C) saturated or aromatic hydrocarbon liquid;or (iii) both (i) and (ii). Alternatively, (iv) the (D) solidparticulate consisting essentially of magnesium halide has been preparedby contacting a solution of (F) a dialkylmagnesium compound dissolved inthe (C) saturated or aromatic hydrocarbon liquid with 1.95 to 2.05 moleequivalents of hydrogen halide (anhydrous) to give a suspension of the(D) solid particulate consisting essentially of magnesium halide in the(C) saturated or aromatic hydrocarbon liquid, wherein thedialkylmagnesium compound is diethylmagnesium, dipropylmagnesium,dibutylmagnesium, butyl-ethyl-magnesium, butyl-octyl-magnesium, or acombination thereof; or (v) both (i) and (iv).

Aspect 8. The method of any one of aspects 1 to 7 wherein the (C) asaturated or aromatic hydrocarbon liquid is: (i) a saturated hydrocarbonliquid; or (ii) an aromatic hydrocarbon liquid; or (iii) a mixture ofsaturated hydrocarbon and aromatic hydrocarbon liquids.

Aspect 9. The method of any one of aspects 1 to 7 wherein the activatorused with the modified Ziegler-Natta procatalyst comprises (A) ahydrocarbylaluminoxane. In some aspects (A) is an alkylaluminoxane, apolymethylaluminoxane, an arylaluminoxane, an aralkylaluminoxane, or acombination of any two or more thereof.

Aspect 10. The method of any one of aspects 2 to 9 wherein the molecularligand-metal complex (pro)catalyst comprises: (i) a cyclopentadienylligand-metal complex (pro)catalyst; (ii) a cyclopentadienyl-freeligand-metal complex (pro)catalyst; or (iii) both (i) and (ii).

Aspect 11. The method of any one of aspects 1 to 10 wherein thecontacting comprises: (i) adding the modified catalyst system into thereactor, which contains the at least one polymerizable olefin; (ii)adding the at least one polymerizable olefin into the reactor, whichcontains the modified catalyst system; or (iii) adding a first feed ofthe modified catalyst system into the reactor and a second feed of theat least one polymerizable olefin into the reactor. The first and secondfeeds may be added sequentially or simultaneously, or partly both.

Aspect 12. A solution phase polymerization process of polymerizing anolefin using a modified catalyst system that is a product of a reactionof a modified Ziegler-Natta procatalyst with an activator, the processcomprising contacting at least one polymerizable olefin in the reactorwith the modified catalyst system under effective conditions to give apolyolefin product; wherein the modified Ziegler-Natta procatalyst isprepared prior to the contacting step by mixing an initial Ziegler-Nattaprocatalyst and a molecular ligand-metal complex precatalyst togetherunder modifying conditions comprising a modifying temperature less than100° C. and a modifying time of at least 1 minute, and optionally anactivator, to give the modified Ziegler-Natta procatalyst. The initialZiegler-Natta catalyst may be (B) a magnesium halide-supported titaniumprocatalyst in (C) a saturated or aromatic hydrocarbon liquid; whereinthe (B) magnesium halide-supported titanium procatalyst has beenprepared by contacting (D) a solid particulate consisting essentially ofmagnesium halide with (E) titanium tetrachloride in the (C) a saturatedor aromatic hydrocarbon liquid so as to give the (B) magnesiumhalide-supported titanium procatalyst. The molecular (pro)catalystconsists essentially of a molecular ligand-metal complex (pro)catalyst.

Aspect 13. A polyolefin product made by the method of any one of aspects1 to 12.

Aspect 14. A modified Ziegler-Natta procatalyst as described in anypreceding aspect.

Aspect 15. The catalyst system of aspect 14 (i) further comprising a (A)hydrocarbylaluminoxane; (ii) further comprising an organoborate or anorganoboron; (iii) further comprising a trialkylaluminum; (iv) beingfree of a trialkylaluminum; (v) both (i) and (ii); (vi) both (i) and(iii); (vii) both (i) and (iv); (viii) each of (i), (ii), and (iv).

Aspect 16. A modified catalyst system comprising a product of a reactionof the modified Ziegler-Natta procatalyst of aspect 14 or 15 with anactivator.

Aspect 17. The modified catalyst system of aspect 16 further comprising(C) a saturated or aromatic hydrocarbon liquid, a polymerizable olefin,a polyolefin, or a combination of any two or more thereof.

Modified Ziegler-Natta procatalyst. The modified Ziegler-Nattaprocatalyst may further comprise an activator. The modifiedZiegler-Natta procatalyst is a product of mixing the initialZiegler-Natta procatalyst with the molecular (pro)catalyst, andoptionally an activator which may be the same as or different than theactivator used with the modified Ziegler-Natta procatalyst to make themodified catalyst system, in such a way that the initial Ziegler-Nattaprocatalyst is modified by the molecular (pro)catalyst such thatpolyolefin composition produced with the modified catalyst system isdifferent than the polyolefin composition that is produced with theinitial Ziegler-Natta procatalyst. The difference in composition mayfound in at least one of the following properties: polyolefin density,polyolefin molecular weight, comonomer distribution, or short chainbranching distribution. The initial Ziegler-Natta procatalyst isprepared prior to the mixing step. The modified catalyst system may beprepared in the reactor or outside of the reactor used in thepolymerization method. The modified Ziegler-Natta procatalyst may beprepared for a modifying time from 1 minute to 24 months, alternatively2 minutes to 12 months, alternatively 3 minutes to 3 months,alternatively 3 hours to 3 months, alternatively 1 month to 24 months,alternatively 1 month to 12 months, alternatively 1 minute to 48 hours,2 minutes to 24 hours, alternatively from 3 minutes to 12 hours beforethe contacting step; and at a modifying temperature from 0° to 100° C.,alternatively 0° to 80° C., 0° to 60° C., alternatively 10° to 55° C.,alternatively 15° to 50° C. The length of modifying time may be adjustedbased on the modifying temperature being used, or vice versa, in such away that the higher the modifying temperature, the shorter may be themodifying time, or vice versa; or the lower the modifying temperature,the longer may be the modifying time, or vice versa.

Molecular (pro)catalyst. The term “(pro)catalyst” means a procatalyst; acatalyst, which is prepared by contacting the procatalyst with at leastone activator; or a combination of the procatalyst and the catalyst. Insome aspects the (pro)catalyst is the procatalyst, alternatively thecatalyst, alternatively the combination of the procatalyst and thecatalyst. Molecular (pro)catalysts for olefin polymerizations arewell-known in the art. The molecular (pro)catalyst may be a homogeneoussingle site (pro)catalyst that, upon activation with an activator, iseffective for polymerizing ethylene and alpha-olefins. The molecular(pro)catalyst generally may exhibit single-site or multi-site behaviorsupon activation with an activator and under polymerization conditions.The molecular (pro)catalyst is distinct from the Ziegler-Nattaprocatalyst in solubility, structure, and composition. The molecular(pro)catalyst may be supported or unsupported; soluble in constituent(C) saturated or aromatic hydrocarbon liquid or insoluble therein. Insome aspects the molecular (pro)catalyst is unsupported. The molecular(pro)catalyst may be selected from any molecular ligand-transition metalcomplex catalyst in which the transition metal is a Group 3 to 11element of the Periodic Table of Elements, including the lanthanides andactinides. The molecular ligand-metal complex (pro)catalyst may be amolecular ligand-metal complex procatalyst, alternatively a molecularligand-metal complex catalyst, alternatively a combination of themolecular ligand-metal complex procatalyst and the molecularligand-metal complex catalyst. In some aspects the transition metal isTi, Zr, Hf, V, or Cr. In some aspects the transition metal is selectedfrom the group of any four of Ti, Zr, Hf, V, and Cr. In some aspects thetransition metal is Fe, Co, Ni, or Pd. In some aspects the transitionmetal is selected from the group of any three of Fe, Co, Ni, and Pd. Insome aspects the molecular (pro)catalyst is a transition metal complex(pro)catalyst useful in solution under high temperature solution processconditions. In some aspects the molecular (pro)catalyst may be selectedfrom any one or more of bis-phenylphenoxy (pro)catalysts, constrainedgeometry (pro)catalysts, imino-amido type (pro)catalysts, pyridyl-amide(pro)catalysts, imino-enamido (pro)catalysts, aminotroponiminato(pro)catalysts, amidoquinoline (pro)catalysts, bis(phenoxy-imine)(pro)catalysts, phosphinimide (pro)catalysts, and metallocene(pro)catalysts.

The molecular procatalyst used in some embodiments to prepare themodified catalyst system may be used to prepare a molecular catalystthat consists essentially of a product of a reaction of a molecularligand-metal complex procatalyst with an activator such as (A) ahydrocarbylaluminoxane and/or (I) a trialkylaluminum and/or (G)organoborate and/or (H) organoboron. The (A) hydrocarbylaluminoxane usedin the reaction to prepare the molecular catalyst independently may bethe same as or different than the (A) hydrocarbylaluminoxane used in areaction to prepare a Ziegler-Natta catalyst from the Ziegler-Nattaprocatalyst.

In some aspects the molecular ligand-metal complex (pro)catalyst is thecyclopentadienyl (Cp) ligand-metal complex (pro)catalyst, which isuseful for preparing so-called metallocene catalysts. Examples ofsuitable cyclopentadienyl ligand-metal complex (pro)catalysts areCp₂ZrCl₂; rac-Et(Ind)₂ZrCl₂, wherein rac means racemic and Et(Ind)₂ is1,2-di(1-indenyl)ethane dianion; iPr(Flu)(Cp)ZrCl₂, wherein iPr(Flu)(Cp)is 9-(alpha,alpha-dimethylcyclopentadienylmethyl)-9H-fluorene dianion.

In some aspects the molecular ligand-metal complex (pro)catalyst is thecyclopentadienyl-free ligand-metal complex (pro)catalyst, which isuseful for preparing so-called post-metallocene catalysts, includingconstrained geometry catalysts. Examples of suitablecyclopentadienyl-free ligand-metal complex (pro)catalysts are aphenoxy-imine ligand-early transition metal complex (pro)catalyst (FI(pro)catalyst), a pyrrolide-imine ligand-Group 4 transition metalcomplex (pro)catalyst (PI (pro)catalyst), an indolide-imine ligand-Ticomplex (II (pro)catalyst), a phenoxy-imine ligand-Group 4 transitionmetal complex (pro)catalyst (IF (pro)catalyst), a phenoxy-etherligand-Ti complex (pro)catalyst (FE (pro)catalyst), an imine-pyridineligand-late transition metal complex (pro)catalyst (IP (pro)catalyst),and a tris(pyrazolyl) borate ligand-Ta complex (pro)catalyst (PB(pro)catalyst).

Additional examples of suitable molecular ligand-metal complex(pro)catalysts are (TTSi)CpTiCl₂, wherein (TTSi)Cp is1,2,3,4-tetramethyl-5-(trimethylamino(dimethyl)silyl) cyclopentadienyl;and the molecular ligand-metal complex (pro)catalysts described in anyone of: U.S. Pat. No. 6,827,976; US 2004/0010103 A1; U.S. Pat. No.8,058,373 B2, at column 11, line 35, to column 16, line 3; complexes offormula (I) described in WO 2016/003878 A1; the fused ring substitutedindenyl metal complexes described in U.S. Pat. No. 6,034,022; theconstrained geometry metal (pro)catalysts referenced in the Backgroundof U.S. Pat. No. 6,034,022; the ligand-metal complexes described in U.S.62/234,910 filed Sep. 30, 2015; the ligand-metal complexes described inU.S. 62/234,791 filed Sep. 30, 2015; a phosphinimine; andbis((2-oxoyl-3-(3,5-bis-(1,1-dimethylethyl)phenyl)-5-(methyl)phenyl)-(5-2-methyl)propane-2-yl)2-phenoxy)-1,3-propanediylzirconium (IV)dimethyl, which is disclosed in WO 2007/136494.

Magnesium halide-supported titanium procatalyst. In some aspects theinitial Ziegler-Natta procatalyst is the (B) magnesium halide-supportedtitanium procatalyst. The magnesium halide-supported titaniumprocatalyst used to make the modified catalyst system may be activatedto give a magnesium halide-supported titanium catalyst by contacting the(B) with an activator that is (A) hydrocarbylaluminoxane, (G)organoborate, (H) organoboron, or a trialkylaluminum compound. Thecontacting may comprise a suspension of (B) in (C) saturated or aromatichydrocarbon liquid and may be done in or under an inert atmosphere(e.g., a gas of molecular nitrogen, argon, helium, or mixture thereof)at 0° to 300° C., alternatively 15° to 250° C. and for a time of from >0minute to 48 hours, alternatively 0.1 minute to 24 hours, alternatively5 to 120 seconds. Examples of suitable trialkylaluminum compounds are offormula (C₁-C₂₀)alkyl)₃Al, wherein each (C₁-C₂₀)alkyl is independentlythe same or different. In some aspects the trialkylaluminum compound istriethylaluminum, triisobutylaluminum, or a combination of any two ormore thereof. The (B) magnesium halide-supported titanium procatalystmay consist essentially of, or consist of, the following elements: Cl,Mg, and Ti; and the suspension of the (B) magnesium halide-supportedtitanium procatalyst in (C) saturated or aromatic hydrocarbon liquid mayconsist essentially of, or consist of, C, H, Cl, Mg, and Ti. When the(B) magnesium halide-supported titanium procatalyst is contacted withthe (A) hydrocarbylaluminoxane, the resulting Ziegler-Natta catalyst isan enhanced Ziegler-Natta catalyst.

Enhanced Ziegler-Natta catalyst. In some aspects the Ziegler-Nattacatalyst is the enhanced Ziegler-Natta catalyst. The enhancedZiegler-Natta catalyst may be made by contacting the (A)hydrocarbylaluminoxane with the suspension of (B) magnesiumhalide-supported titanium procatalyst in (C) saturated or aromatichydrocarbon liquid so as to activate the (B) magnesium halide-supportedtitanium procatalyst and give the enhanced catalyst. The formation ofthe enhanced catalyst may be done in situ in a polymerization reactor orjust prior to entering the polymerization reactor. The contacting of (A)with suspension of (B) in (C) may be done in or under an inertatmosphere (e.g., a gas of molecular nitrogen, argon, helium, or mixturethereof) at 0° to 300° C., alternatively 15° to 250° C. and for a timeof from >0 minute to 48 hours, alternatively 0.1 minute to 24 hours,alternatively 5 to 120 seconds. The catalytic activity of the enhancedcatalyst is greater than the catalytic activity of a magnesiumhalide-supported titanium catalyst prepared by contacting (B) with thetrialkylaluminum compound. In some aspects catalytic activity of theenhanced catalyst may be further enhanced by also contacting (B) and (A)with the (G) organoborate or the (H) organoboron. The enhanced catalystmay consist essentially of, or consist of, the following elements: Al,C, H, Cl, Mg, O, and Ti.

In some aspects the enhanced catalyst and the (B) magnesiumhalide-supported titanium procatalyst, used to make the enhancedZiegler-Natta catalyst, are independently characterized by a molar ratioof Ti to halogen. For example, 0≤(N_(X)−80−4*N_(Ti))≤6, alternatively0≤(N_(X)−80−4*N_(Ti))≤4, alternatively 0≤(N_(X)−80−4*N_(Ti))≤2; whereinN_(Ti)=moles of Ti per 40 moles of Mg in the catalyst and N_(X)=moles ofhalogen per 40 moles of Mg in the catalyst. In some aspects X is Cl,alternatively Br.

The (A): hydrocarbylaluminoxane or HAO. The alkylaluminoxane may be apolymeric form of a (C₁-C₁₀)alkylaluminoxane or a polymethylaluminoxane(PMAO). The PMAO may be a polymethylaluminoxane-Improved Performance(PMAO-IP), which is commercially available from AkzoNobel. The(C₁-C₁₀)alkylaluminoxane may be methylaluminoxane (MAO), a modifiedmethylaluminoxane (MMAO) such as modified methylaluminoxane, type 3A(MMAO-3A), type 7 (MMAO-7), or type 12 (MMAO-12), ethylaluminoxane,n-propylaluminoxane, isopropylaluminoxane, butylaluminoxane,isobutylaluminoxane, n-pentylaluminoxane, neopentylaluminoxane,n-hexylaluminoxane, n-octylaluminoxane, 2-ethylhexylaluminoxane,cyclohexylaluminoxane, or 1-methylcyclopentylaluminoxane. Thearylaluminoxane may be a (C₆-C₁₀)arylaluminoxane, which may bephenylaluminoxane, 2,6-dimethylphenylaluminoxane, ornaphthylaluminoxane. The aralkylaluminoxane may be benzylaluminoxane orphenethylaluminoxane. Typically, the compound (A) is MAO, MMAO, PMAO, orPMAO-IP. The hydrocarbylaluminoxane may be made by a non-hydrolyticprocess using, or by partial hydrolysis of, trihydrocarbylaluminumcompounds according to well-known methods or may be obtained from acommercial source.

The magnesium halide-supported titanium procatalyst. The magnesiumhalide-supported titanium procatalyst may be any Ziegler-Nattaprocatalyst that, upon activation, is effective for catalyzingpolymerization of ethylene and alpha-olefins. The magnesiumhalide-supported titanium procatalyst may be prepared by adding atitanium halide to a magnesium chloride support or by converting atitanium compound (e.g., a titanium tetraalkoxide such as a titaniumtetraisopropoxide) and magnesium compound (e.g., dialkylmagnesium) intotheir respective metal halide forms. In some aspects the magnesiumhalide-supported titanium procatalyst is the inventive (B) magnesiumhalide-supported titanium procatalyst. The preparation (B) may comprisethe step of contacting (D) a solid particulate consisting essentially ofmagnesium halide with (E) titanium tetrachloride in (C) a saturated oraromatic hydrocarbon liquid to give the (B). The preparation may be donein or under an inert atmosphere (e.g., a gas of molecular nitrogen,argon, helium, or mixture thereof) at 0° to 100° C., alternatively 20°to 35° C. and for a time of from 0.1 minute to 24 hours, alternatively 5to 12 hours. The (D) used to prepare the (B) may be prepared asdescribed below. The suspension of (B) in (C) may be used in the nextstep without being separated from each other. When prepared in this wayit is not necessary to separate the (B) from the (C) and a suspension ofthe (B) in (C) a saturated or aromatic hydrocarbon liquid may be useddirectly, in a one-pot syntheses, with the trialkylaluminum compound orthe (A) hydrocarbylaluminoxane to prepare the magnesium halide-supportedtitanium catalyst or the enhanced catalyst, respectively. (In contrast,additional alkylaluminum halide or aluminum halide compound(s) aretypically used to prepare a standard (non-inventive) halide-containingZiegler-Natta catalyst.) In some aspects, the magnesium halide-supportedtitanium procatalyst may be any conventional Ziegler-Natta procatalyst.In some aspects, the conventional magnesium halide-supported titaniumprocatalyst may be a Ziegler-Natta procatalyst comprising titaniumchloride, MgCl₂, and optionally one or more transition metals (e.g., anelement of any one of Groups 4 to 13 of the Periodic Table of theElements). In some aspects the magnesium halide-supported titaniumprocatalyst may be the inventive (B) magnesium halide-supported titaniumprocatalyst. The (B) may be distinguished from a conventional magnesiumhalide-supported titanium procatalysts by virtue of how (B) is prepared,as described herein.

A polyolefin prepared by a polymerization reaction using a standardhalide-containing Ziegler-Natta catalyst may have a higher residualactive halide content. The actual content may vary within limits asfollows: proportionally with the starting halide content in thecorresponding standard Ziegler-Natta procatalyst and/or inverselyproportional with the activity of the Ziegler-Natta catalyst preparedtherefrom. In some aspects the magnesium halide-supported titaniumprocatalyst has been prepared in such a way so as to have a low residualactive halide content, such as in the (B), and thus the magnesiumhalide-supported titanium catalyst prepared therefrom with thetrialkylaluminum compound and the enhanced catalyst prepared therefromwith the (A) hydrocarbylaluminoxane also have low residual active halidecontent, and thus the product polyolefin prepared by the polymerizationmethod using the modified catalyst system also has low residual activehalide content. Active halide impurity means a metal-halide containingcompound that, when exposed to moisture or water under ambientconditions (e.g., 25° C. and 101 kPa pressure) undergoes a hydrolysisreaction yielding a hydrogen halide (e.g., HCl).

In some aspects the (B) magnesium halide-supported titanium procatalysthas a total metal content of 94 to 100 mol %, alternatively 96 to 100mol %, alternatively 98 to 99.5 mol % of Ti and Mg. The suspension of(B) magnesium halide-supported titanium procatalyst in (C) saturated oraromatic hydrocarbon liquid may consist essentially of, or consist of,the following elements: C, H, Cl, Mg, and Ti.

The (C) saturated or aromatic hydrocarbon liquid. The compound (C)saturated or aromatic hydrocarbon liquid may be any unsubstitutedsaturated or aromatic hydrocarbon liquid such as an unsubstitutedaromatic hydrocarbon or an unsubstituted alkane. The unsubstitutedaromatic hydrocarbon may be toluene or xylene(s). The unsubstitutedalkane may be a straight chain alkane, a branched chain alkane such asan isoalkane or mixture of isoalkanes such as ISOPAR E, a cycloalkanesuch as cycloheptane or methylcyclohexane, or a mixture of any two ormore thereof. Suitable (C) saturated or aromatic hydrocarbon liquid areavailable from commercial sources such as isoalkanes available fromExxonMobil Corp.

In some aspects the (C) saturated or aromatic hydrocarbon liquid inwhich a first product is prepared may be removed from the first product,and a different (C) material combined with the first product prior topreparing the next product therefrom. The removing may be by methodssuch as stripping, evaporating, distilling, filtering, or “solvent”exchanging. In other aspects at least some of the (C) saturated oraromatic hydrocarbon liquid in which a first product is prepared iscarried through with the first product to a preparation of a nextproduct, which is prepared from the first product, without all or any ofthe (C) being removed from the first product. This carry through may beaccomplished using one-pot preparation methods, which are generally wellknown in the art. The following examples (i) to (v) of the latteraspects may use one-pot preparation methods: (i) the (C) saturated oraromatic hydrocarbon liquid in which the (D) solid particulate isprepared (see below) may be the same as the (C) saturated or aromatichydrocarbon liquid in which the magnesium halide-supported titaniumprocatalyst is prepared, such as the (C) in which the inventive (B)magnesium halide-supported titanium procatalyst is prepared; (ii) the(C) saturated or aromatic hydrocarbon liquid in which the (B) magnesiumhalide-supported titanium procatalyst is prepared may be the same as the(C) saturated or aromatic hydrocarbon liquid in which the inventiveenhanced catalyst is prepared; (iii) the (C) saturated or aromatichydrocarbon liquid in which the magnesium halide-supported titaniumprocatalyst (such as (B)) is prepared may be the same as the (C)saturated or aromatic hydrocarbon liquid in which the modifiedZiegler-Natta procatalyst is prepared; (iv) the (C) saturated oraromatic hydrocarbon liquid in which the modified Ziegler-Nattaprocatalyst is prepared may be the same as the (C) saturated or aromatichydrocarbon liquid in which the modified catalyst system is prepared; or(v) any two or more of examples (i) to (iv), e.g., (i) and (ii), (ii)and (iii), (iii) and (iv), or all of (i) to (iv).

The (D) solid particulate consisting essentially of magnesium halide.The compound (D) is prepared as described above. The contacting asolution of (F) a dialkylmagnesium compound dissolved in (C) saturatedor aromatic hydrocarbon liquid with 1.95 to 2.05 mole equivalents ofhydrogen halide to give the (D) solid particulate consisting essentiallyof magnesium halide may be done in or under an inert atmosphere (e.g., agas of molecular nitrogen, argon, helium, or mixture thereof) at −25° to100° C., alternatively 0° to 50° C. and for a time of from 0.1 minute to10 hours, alternatively 1 to 6 hours. The suspension of (D) in (C) maybe used without being separated from each other. It is not necessary toseparate the (D) from the (C) and the (D) prepared in this way isunconditioned and may be used directly, in a one-pot syntheses, toprepare the (B) magnesium halide-supported titanium procatalyst.Alternatively, the (D) may be conditioned by contacting it with aconditioning compound containing V, Zr, or Hf at 0° to 50° C.,alternatively 20° to 35° C., and for a time of from 0.1 minute to 24hours, alternatively 1 to 12 hours to form a conditioned (D). Thesuspension of conditioned (D) in (C) may be used without being separatedfrom each other. It is not necessary to separate the conditioned (D)from the (C) and the conditioned (D) prepared in this way may be useddirectly, in a one-pot syntheses, to prepare the (B) magnesiumhalide-supported titanium procatalyst. When prepared in this way asuspension of the (D), unconditioned or conditioned, in (C) saturated oraromatic hydrocarbon liquid may be contacted with (E) titaniumtetrachloride so as to give the (B) magnesium halide-supported titaniumprocatalyst.

The (D) solid particulate consisting essentially of magnesium halide mayhave a BET surface area of ≥200 m²/g, alternatively >250 m²/g,alternatively >300 m²/g; and a maximum BET surface area of 1,500 m²/g,alternatively 1,000 m²/g, alternatively 500 m²/g, alternatively 300m²/g, all as measured by the BET Surface Area Method. When the halide ischloride, the magnesium halide is MgCl₂ and when the halide is bromide,the magnesium halide is MgBr₂.

The suspension of (D) solid particulate consisting essentially ofmagnesium halide in (C) saturated or aromatic hydrocarbon liquid mayconsist essentially of, or consist of, the following elements: C, H, Cl,and Mg. The suspension of (D) may have a halide to magnesium ratio of1.5 to 2.5, alternatively 1.8 to 2.2, alternatively 1.95 to 2.05.

The (E) titanium tetrachloride is a compound of formula TiCl₄, or asolution of TiCl₄ in a saturated or aromatic hydrocarbon liquid such asa same or different compound (C) saturated or aromatic hydrocarbonliquid. TiCl₄ and the solution thereof are available from commercialsources or may be readily prepared by well-known methods.

The (F) dialkylmagnesium compound may be of formula (I): R¹MgR² (I),wherein each of R¹ and R² is independently an unsubstituted(C₁-C₂₀)alkyl group, alternatively an unsubstituted (C₁-C₁₀)alkyl group,alternatively an unsubstituted (C₁-C₄)alkyl group. In some aspects thedialkylmagnesium compound is an unsubstituted (C₁-C₄)alkyl group, whichis dimethylmagnesium, diethylmagnesium, dipropylmagnesium,isopropyl-methyl-magnesium (i.e., (CH₃)₂CHMgCH₃), dibutylmagnesium,butyl-ethyl-magnesium (i.e., CH₃(CH₂)₃MgCH₂CH₃), butyl-octyl-magnesium(i.e., CH₃(CH₂)₃Mg(CH₂)₇CH₃), or a combination thereof. Dialkylmagnesiumcompounds are available commercially or may be readily prepared bywell-known methods.

The (G) organoborate. Compound (G) may be any organoborate that enhancesthe method of polymerization using ethylene monomer. In some aspectscompound (G) is a methyldi((C₁₄-C₁₈)alkyl)ammonium salt oftetrakis(pentafluorophenyl)borate, which may be prepared by reaction ofa long chain trialkylamine (Armeen™ M2HT, available from Akzo-Nobel,Inc.), HCl and Li[B(C₆F₅)₄]. Such a preparation is disclosed in U.S.Pat. No. 5,919,983, Ex. 2. Or the borate is purchased from BoulderScientific. The borate may be used herein without (further)purification.

The (H) organoboron. Compound (H) may be any organoboron that enhancesthe method of polymerization using ethylene monomer. In some aspectscompound (E) is a tris(perfluoroaryl)borane such astris(pentafluorophenyl)borane.

The (I) trialkylaluminum. The trialkylaluminum may be of formula((C₁-C₁₀)alkyl)₃Al, wherein each (C₁-C₁₀)alkyl is independently the sameor different. Each (C₁-C₁₀)alkyl may be methyl, ethyl, propyl,1-methylethyl, butyl, 1-methylpropyl, hexyl, or octyl. E.g.,triethylaluminum, triisobutylaluminum, tripropylaluminum,tributylaluminum, trihexylaluminum, or trioctylaluminum.

The (J) conditioning compound. The (J) conditioning compound may bezirconium-based, hafnium-based, or vanadium based. E.g.,tetrakis(2,2,6,6-tetramethyl-3,5-heptanedionato)zirconium, zirconiumtetraisopropoxide,tetrakis(2,2,6,6-tetramethyl-3,5-heptanedionato)hafnium, hafniumtetrapropoxides,tetrakis(2,2,6,6-tetramethyl-3,5-heptanedionato)vanadium, or vanadiumtetrapropoxide. Functions to increase Mz/Mw ratio of product polyolefinproduced by the polymerization method relative to Mz/Mw ratio of aproduct polyolefin produced by the polymerization method lacking (J).

Hydrogen halide. The halide of the hydrogen halide used to prepare the(B) magnesium halide-supported titanium procatalyst is the same as thehalide of the magnesium halide of the (B) magnesium halide-supportedtitanium procatalyst. E.g., both are chloride, alternatively both arebromide. Anhydrous. The mole equivalents of hydrogen halide to (F)dialkylmagnesium compound may be 2.00 to 2.05.

Polymerizable olefins. Examples of suitable polymerizable olefinsinclude ethylene (CH₂CH₂) and (C₃-C₄₀)alpha-olefins. The polymerizableolefin may comprise a mixture of ethylene and a (C₃-C₄₀)alpha-olefin.The (C₃-C₄₀)alpha-olefin may be from 0.1 wt % to 20 wt %, alternativelyfrom 0.1 to 15 wt %, alternatively 0.1 to 10 wt %, alternatively 0.1 to5 wt % of the mixture and ethylene the remainder. The(C₃-C₄₀)alpha-olefin may be a (C₃-C₂₀)alpha-olefin, alternatively a(C₃-C₁₂)alpha-olefin, alternatively a (C₃-C₈)alpha-olefin. Examples ofthe (C₃-C₈)alpha-olefin are propene, 1-butene, 1-hexene, and 1-octene.The modified Ziegler-Natta catalyst and/or the molecular catalyst may beused to polymerize ethylene to give a polyethylene. Alternatively, themodified Ziegler-Natta catalyst and/or the molecular catalyst may beused to polymerize a (C₃-C₄₀)alpha-olefin to give apoly((C₃-C₄₀)alpha-olefin) polymer. Alternatively, the modifiedZiegler-Natta catalyst and/or the molecular catalyst may be used tocopolymerize ethylene and at least one (C₃-C₄₀)alpha-olefin to give apoly(ethylene-co-(C₃-C₄₀)alpha-olefin) copolymer. Polymerizations may bedone in any suitable rector such as a batch reactor or in a continuousreactor such as a continuous solution polymerization reactor.

Method of polymerizing an olefin. In the polymerization method, themodified Ziegler-Natta procatalyst may be used as one would use astandard Ziegler-Natta procatalyst to catalyze, upon activation with anactivator, polymerization of at least one (e.g., 1, 2, or more)polymerizable olefins. The molecular (pro)catalyst may be used to modifya standard Ziegler-Natta procatalyst to prepare the modifiedZiegler-Natta procatalyst. The molecular (pro)catalyst may also be usedas one would use a standard molecular (pro)catalyst to catalyze, uponactivation with an activator, polymerization of at least one (e.g., 1,2, or more) polymerizable olefins. The modified Ziegler-Nattaprocatalyst and molecular procatalyst, once activated, independently maycatalyze polymerization of the same or different polymerizable olefins.The method may be a slurry polymerization process conducted at atemperature from 0° to 100° C. Alternatively, the method may be a gasphase polymerization process conducted at a temperature from 30° to 120°C. Alternatively, and typically, the method may be a solution phasepolymerization process conducted at a temperature from 100° to 250° C.The pressure may be 150 psi to 3,000 psi (1 megapascal (MPa) to 21 MPa).

The method of polymerizing an olefin may be carried out in a reactionmixture containing at least one polymerizable olefin and the modifiedZiegler-Natta catalyst, which is prepared by contacting the modifiedZiegler-Natta procatalyst with one or more activators (e.g., with (A),alternatively with (G), alternatively with (A) and (G), alternativelywith (G) followed by (A). The reaction mixture may contain an additionalamount of (C) saturated or aromatic hydrocarbon liquid as a diluent orsolvent so as to avoid oversaturating the (C) with polymer product, andthereby reducing catalyst efficiency. In some aspects the amount ofpolymer product in the reaction mixture is less than or equal to 30 wt%. The reaction mixture may be agitated (e.g., stirred) and thetemperature of the reaction mixture may be controlled by removing heatof reaction therefrom so as to optimize the polymerization. In themethod of polymerizing an olefin the modified Ziegler-Natta catalyst isused in a catalytically effective amount, such as from 0.0001 to 0.1milligram-atoms of Ti per liter (L) of the reaction mixture. The methodof polymerizing an olefin may be a batch method, semi-continuous method,or a continuous method. The continuous method continuously suppliesreactants to the reactor and removes polymer product from the reactor.The semi-continuous method periodically adds reactants to the reactorand periodically removes polymer product from the reactor. The batchmethod adds reactants to the reactor and then removes polymer productfrom the reactor after the reaction is finished.

An example of a method of polymerizing uses a stirred-tank reactor, intowhich the polymerizable olefin(s) are introduced continuously togetherwith any additional amount of (C) (C) saturated or aromatic hydrocarbonliquid. The reactor contains a liquid phase composed substantially ofethylene, and optionally a (C₃-C₄₀)alpha-olefin, (C) and dissolvedpolymer product. The catalysts and/or their procatalysts and activatorsare continuously or intermittently introduced into the reactor liquidphase, or any recycled portion thereof. The reactor temperature andpressure may be controlled by adjusting the solvent/olefin ratio, thecatalyst addition rate, as well as by cooling or heating coils, jacketsor both. The extent of the reaction may be controlled by the rate ofcatalyst(s) addition. The ethylene content of the polymer product isdetermined by the ratio of ethylene to (C₃-C₄₀)alpha-olefin, if any, inthe reactor, which is controlled by manipulating the respective feedrates of these components to the reactor. The polymer product'smolecular weight is controlled, optionally, by controlling otherpolymerization variables such as the temperature, olefinconcentration(s), or by feeding molecular hydrogen at a controlled rateinto the reactor. If used, the molecular hydrogen may have aconcentration of 0.001 to 1 mole percent per 1 mole of ethylene. Uponexiting the reactor, the effluent containing product polymer (productpolyolefin composition) may be contacted with a catalyst kill agent suchas water, steam or an alcohol. The product polymer mixture is optionallyheated, and the polymer product recovered by flashing off gaseous orvaporous components such as ethylene, alpha olefin, and component (C),optionally under reduced pressure. If desired, further devolatilizationmay be done in a devolatilizing extruder. In the continuous process themean residence time of the catalyst and product polymer in the reactorgenerally is 1 minute to 8 hours, and alternatively 5 minutes to 6hours. Alternatively, a continuous loop reactor such as in U.S. Pat.Nos. 5,977,251; 6,319,989; or 6,683,149 and ad rem conditions may beused instead of the stirred tank reactor.

In some aspects the method of polymerizing an olefin is a solution phaseprocess.

Polyolefin product made by the method of polymerizing an olefin. Theproduct comprises a polyolefin composition comprising polyolefinmacromolecules. The polyolefin product may be a polymer or copolymer.The polymer may be a homopolymer such as polyethylene, apoly((C₃-C₄₀)alpha-olefin) polymer such as polypropylene. The copolymermay be a poly(ethylene-co-(C₃-C₄₀)alpha-olefin) copolymer such as apoly(ethylene-co-propene) copolymer, a poly(ethylene-co-1-butene)copolymer, a poly(ethylene-co-1-hexene) copolymer, or apoly(ethylene-co-1-octene) copolymer. The polyethylene may be a highdensity polyethylene (HDPE), linear low density polyethylene (LLDPE),medium density polyethylene (MDPE), high melt strength high densitypolyethylene (HMS-HDPE), or a combination of any two or more thereof.

The polyolefin polymer or copolymer may further include one or moreadditives such as antistatic agents, color enhancers, dyes, lubricants,fillers, pigments, primary antioxidants, secondary antioxidants,processing aids, and ultraviolet (UV) light stabilizers. The resultingadditive containing polyolefin (co)polymer may comprise from 0 wt % to10 wt % of each additive, based on the weight of the additive containingpolyolefin (co)polymer. Antioxidants, such as Irgafos™ 168 and Irganox™1010, may be used to protect the polyolefin (co)polymer from thermaland/or oxidative degradation. Irganox™ 1010 is tetrakis (methylene(3,5-di-tert-butyl-4hydroxyhydrocinnamate) available from Ciba GeigyInc. Irgafos™ 168 is tris (2,4 di-tert-butylphenyl) phosphite availablefrom Ciba Geigy Inc.

The polyolefin product made by the method may comprise a first polymerand a second polymer, which is different than the first polymer. Thefirst polymer may be primarily produced by a first reaction catalyzed bythe Ziegler-Natta catalyst, which is prepared by contacting the initialZiegler-Natta procatalyst with at least one activator (e.g., (A) or both(G) and (A)). The second polymer may be primarily produced by a secondreaction catalyzed by the molecular catalyst, which is prepared bycontacting the molecular ligand-metal complex (pro)catalyst with atleast one activator (e.g., (A) or (I)). The ratio of first polymer tosecond polymer in the polyolefin product may be controlled bycontrolling the selection and relative amount of the initialZiegler-Natta procatalyst to the molecular (pro)catalyst, or bycontrolling the selection and amount of activator used to prepare theinitial Ziegler-Natta catalyst and controlling the selection and amountof the activator used to prepare the molecular catalyst.

The polymer product may have a weight average molecular weight (Mw) from50,000 to 300,000 grams/mole (g/mol). The polymer product may have apolymer density from 0.880 to 0.970 g/cc, alternatively 0.890 to 0.960g/cc (gram per cubic centimeter).

The polyolefin product may be used in a forming operation to preparemanufactured articles from or comprising the polyolefin product.Examples of such forming operations are film forming, sheet forming,pipe forming, fiber extruding, fiber co-extruding, blow molding,injection molding, and rotary molding. The manufactured articlesprepared thereby may be blown or cast films, such as films formed byco-extrusion or lamination; fibers such as melt spun fibers and meltblown fibers for use in non-woven and woven fabrics; extruded articles;and molded articles. The films may be made as shrink films, cling films,stretch films, sealing films, oriented films, snack packaging films,heavy duty bags, grocery sacks, baked and frozen food packaging, medicalpackaging, industrial liners, agricultural films, and membranes such asfood-contact and non-food-contact membranes. The fibers may be made foruse in diaper fabrics, medical garments, and geotextiles. The extrudedarticles may be made as medical tubing, wire and cable coatings,geomembranes, and pond liners. The molded articles may be made asbottles, tanks, large hollow articles, rigid food containers, and toys.

The aspects herein have numerous advantages. One of the advantages isthat the modified catalyst system may produce a polyolefin compositionthat is different than a polyolefin composition obtained from using aZiegler-Natta catalyst alone.

Another advantage is the modified catalyst system in one part in asingle reactor in a solution phase polymerization process, eliminatingthe need for separate catalyst feeds, separate reactors, and specializedequipment relating thereto.

Another advantage is that the polyolefin composition produced by themodified catalyst system may have at least one of the following improvedproperties: polymer density, polymer molecular weight, comonomerdistribution, and short chain branching distribution.

“Activator” (sometimes referred to as a co-catalyst) means a compoundthat is effective for reacting with a procatalyst to give a catalyst,which is catalytically active. Examples of activators are the (A)hydrocarbylaluminoxane, (G) organoborate, (H) organoboron, (I)trialkylaluminum, and a combination of any two or more thereof. E.g., acombination of (A) and (G), alternatively (A) and (H), alternatively (A)and (I), alternatively (G) and (I). In some aspects the combination of(G) and (A) is used. In some aspects (G) is used first, followed by (A);alternatively (A) followed by (G).

The phrase “early transition metal” means an element of any one ofGroups 3 to 5. The phrase “late transition metal” means an element ofany one of Groups 8 to 11.

As used here “procatalyst” (also may be referred to as a precatalyst)means a material that may exhibits no or low polymerization activity(e.g., catalyst efficiency may be 0 or <1,000) in the absence of anactivator (e.g., (A), (G), (H), and/or (I)), but upon activation with anactivator (e.g., (A), (G), (H), and/or (I)) yields a catalyst that showsat least 10 times greater catalyst efficiency than that of theprocatalyst.

In some aspects the (D) solid particulate consisting essentially ofmagnesium halide, and the suspension of (D) in the (C) saturated oraromatic hydrocarbon liquid, and the (B) magnesium halide-supportedtitanium procatalyst prepared from the (D) solid particulate consistingessentially of magnesium halide, and the suspension of the (B) magnesiumhalide-supported titanium procatalyst in the compound (C) saturated oraromatic hydrocarbon liquid, and the enhanced catalyst prepared from thesuspension of the (B) magnesium halide-supported titanium procatalyst inthe compound (C) saturated or aromatic hydrocarbon liquid and the (A)hydrocarbylaluminoxane, collectively “inventive materials”, are purerthan their counterpart standard materials. The greater purity of theinventive materials is due in part by virtue of how they arerespectively prepared, as described earlier, e.g., having a lower activehalide impurity content. For example, the respective present methods ofpreparing the inventive materials (B) and enhanced catalyst avoid usingalkylaluminum compounds and aluminum halide compounds, whereas at leastsome counterpart standard materials may have been prepared usingalkylaluminum compounds and aluminum halide compounds, which generateundesired by-products. Also, the preparation of the enhanced catalystusing the (A) hydrocarbylaluminoxane with the inventive suspension ofthe (B) magnesium halide-supported titanium procatalyst in the compound(C) saturated or aromatic hydrocarbon liquid is an improvement overstandard preparations aluminum halide compound. As used herein, thephrases “consisting essentially of” and “consists essentially of” arepartially closed-ended phrases that capture the greater purities of theinventive materials and in this context may mean having 0 mol %,alternatively having >0 mol % to <5 mol %, alternatively >0 mol % to <3mol %, alternatively >0 mol % to <2 mol % of a material other than thelisted materials that follow the phrases, or reactants used to preparethose listed materials.

EXAMPLES

Brunauer, Emmett, Teller (BET) Surface Area Method: Measure surface areawith a Tristar 3020 Surface Area Analyzer by Micromeritics. Filter 30 mLof a MgCl2 slurry, reslurry in 30 mL hexane, filter the reslurry underinert atmosphere, wash with additional hexane. Repeat the reslurrying,filtering, and washing steps to obtain a filtercake of MgCl2. Removeresidual solvent from filtercake under a first vacuum. Further dry thefiltercake on a Vac Prep 061 by Micromeritics using a 0.5 inch (1.27 cm)sample tube and a Transeal stopper designed for inert sample protectionby loading a 0.2 g sample of the first vacuum-dried MgCl2 into the tubeunder inert atmosphere and stoppered with Transeal stopper. Connect tubeto Vac Prep 061 unit, purging with nitrogen gas while connecting sample.Open Transeal stopper, place tube's contents under second vacuum, placeevacuated tube in heating block with an aluminum tube protector. Dryunder second vacuum on Vac Prep 061 at 110 C. for 3 hours, introducenitrogen gas into tube, and allow sample to cool to room temperaturebefore disconnecting tube from Vac Prep 061 to give fully dried sample.Under inert atmosphere, transfer 0.1500 to 0.2000 g of fully driedsample into a clean sample tube, place tube filler rod in tube, sealtube with Transeal stopper, connect to Tristar 3020, and measure surfacearea. Use QUICKSTART method to acquire the data.

Gel Permeation Chromatography (GPC) Method. Instrument: PolymerCharGPC-IR (Valencia, Spain) high temperature GPC chromatograph equippedwith an internal IRS detector, autosampler, and PolymerChar GPCOne™software. Temperatures: autosampler oven compartment at 160° C. andcolumn compartment at 150° C. Chromatographic solvent: Nitrogen-sparged1,2,4 trichlorobenzene that contains 200 parts per million (ppm) ofbutylated hydroxytoluene (BHT). Injection volume: 200 microliters (μL).Flow rate 1.0 μL/minute. Columns: 3 Agilent “Mixed B” 30 centimeter(cm)×10-micrometer (μm) linear mixed-bed columns and a 10-μm pre-column.Prepare samples using the autosampler targeting 2 milligrams sample permilliliter solvent (mg/mL) in a septa-capped vial that has been nitrogensparged, and shaking the vial at low speed for 2 hours at 160° C.

GPC Method continued: Calibrate columns with 21 narrow MWD polystyrene(PS) standards from Agilent Technologies and having molecular weights(MW) 580 to 8,400,000 g/mol and arranged in 6 “cocktail” mixtures withat least a decade separation between Mw. Prepare PS standards at 0.025 gin 50 milliliters (mL) of solvent for MW≥1,000,000 g/mol and 0.05 g/mLsolvent for MW<1,000,000 g/mol. Convert PS standard peak MW topolyethylene MW as described in Willams and Ward, J. Polym. Sci., Polym.Lett., 1968; 6: 621, using Equation EQ1:M_(polyethylene)=A×(M_(polystyrene))^(B) EQ1, wherein M is molecularweight, A equals 0.4315, and B equals 1.0. Use fifth order polynomial tfit respective polyethylene-equivalent calibration points. Make a smalladjustment to A (from about 0.415 to 0.44) to correct for columnresolution and band-broadening effects such that MW for NIST standardNBS 1475 is obtained at 52,000 g/mol. Monitor deviations over time usinga flow rate marker, e.g., decane, in each sample (introduced viamicropump) to align flow rate marker peak from sample to flow ratemarker peak of PS standards. Use flow rate marker to linearly correctflow rate for each sample by aligning respective sample flow rate markerpeaks to respective PS standards flow rate marker peaks. Assume anychanges in time of the flow rate marker peak are related to a linearshift in flow rate and chromatographic slope. For best accuracy of RVmeasurement of the flow rate marker peak, use a least-squares fittingroutine to fit the flow rate marker peak of a flow rate markerconcentration chromatogram to a quadratic equation. Use PolymerCharGPCOne™ software to process flow rate marker peak.

GPC Method continued: Measure total plate count (Equation EQ2) andsymmetry (Equation EQ3) of GPC columns with 0.04 g eicosane dissolved in50 mL of TCB. EQ2: Plate Count=5.54*[(RV_(Peak Max)) divided by (PeakWidth at ½ height)]², wherein RV is retention volume (mL), peak width isin mL, peak max is maximum height of peak, and ½ height is half heightof peak maximum.

$\begin{matrix}{{{Symmetry} = \frac{\left( {{{Rear}\mspace{14mu}{Peak}\mspace{14mu}{RV}_{{one}\mspace{14mu}{tenth}\mspace{14mu}{height}}} - {RV}_{{Peak}\mspace{14mu}\max}} \right)}{\left( {{RV}_{{Peak}\mspace{14mu}\max} - {{Front}\mspace{14mu}{Peak}\mspace{14mu}{RV}_{{one}\mspace{14mu}{tenth}\mspace{14mu}{height}}}} \right)}},\text{:}} & {EQ3}\end{matrix}$

wherein RV and peak width are as defined above, peak max is the maximumposition of the peak, one tenth height is 1/10 height of the peakmaximum, rear peak is the peak tail at later retention volumes thanthose of the peak max, and front peak refers to the peak front atearlier retention volumes than the peak max. Plate count shouldbe >24,000 and symmetry should be >0.98 to <1.22.

GPC Method continued: Calculate number average molecular weight (Mn),weight average molecular weight (Mw), and z-average molecular weight(Mz) from GPC results from using internal IR5 detector (measurementchannel) of the PolymerChar GPC-IR instrument and PolymerChar GPCOne™software. Baseline-subtract the IR chromatogram at each equally-spaceddata collection point (i), and obtain the polyethylene equivalent Mn,Mw, and Mz from the narrow standard calibration curve for the same point(i) from EQ1.

Crystallization Elution Fraction (CEF) Method is conducted according toMonrabal et al, Macromol. Symp. 257, 71-79 (2007). Equip a CEFinstrument with an IR-4 or IR-5 detector (such as that sold commerciallyfrom PolymerChar, Spain) and a two-angle light scattering detector Model2040 (such as those sold commercially from Precision Detectors). Installa 10 micron guard column of 50 mm×4.6 mm (such as that sold commerciallyfrom PolymerLabs) before the IR-4 or IR-5 detector in a detector oven.Use ortho-dichlorobenzene (ODCB, 99% anhydrous grade) and2,5-di-tert-butyl-4-methylphenol (BHT) (such as commercially availablefrom Sigma-Aldrich) and silica gel 40 (particle size 0.2˜0.5 mm) (suchas commercially available from EMD Chemicals). Dry the silica gel in avacuum oven at 160° C. for at least two hours before use. Sparge theODCB with dried nitrogen (N₂) gas for one hour before use. Further drythe ODCB by adding five grams of the dried silica to two liters of ODCBor by pumping the ODCB through a column or columns packed with driedsilica at a flow rate between 0.1 mL/min. to 1.0 mL/min. Add 800milligrams (mg) of BHT to two liters of ODCB if no inert gas such as N₂is used in purging a sample vial. Dried ODCB, with or without BHT, ishereinafter referred to as “ODCB-m”. Prepare a sample solution using theautosampler by dissolving a polymer sample in ODCB-m at 4 mg/mL withshaking at 160° C. for 2 hours. Inject 300 μL of the sample solutioninto the column. Use a temperature profile: crystallization at 3°C./min. from 110° to 30° C., thermal equilibrium at 30° C. for 5 minutes(including Soluble Fraction Elution Time being set as 2 minutes), andelution at 3° C./min. from 30° to 140° C. Use a flow rate duringcrystallization of 0.052 mL/min and a flow rate during elution of 0.50mL/min. Collect 1 data point of IR-4 or IR-5 signal data/second.

CEF Method continued. Pack a column with glass beads at 125 μm±6% (suchas those commercially available with acid wash from MO-SCI SpecialtyProducts) with ⅛ inch stainless tubing according to U.S. Pat. No.8,372,931. The internal liquid volume of the CEF column is between 2.1mL and 2.3 mL. Perform temperature calibration using a mixture of NISTStandard Reference Material linear polyethylene 1475a (1.0 mg/mL) andEicosane (2 mg/mL) in ODCB-m. The calibration consists of: (1)calculating the delay volume defined as the temperature offset betweenthe measured peak elution temperature of Eicosane minus 30.00° C.; (2)subtracting the temperature offset of the elution temperature from theCEF raw temperature data (the temperature offset is a function ofexperimental conditions, such as elution temperature, elution flow rate,etc.); (3) creating a linear calibration line transforming the elutiontemperature across a range of 30.00° to 140.00° C. such that NIST linearpolyethylene 1475a has a peak temperature at 101.00° C. and Eicosane hasa peak temperature of 30.00° C.; (4) for the soluble fraction measuredisothermally at 30° C., linearly extrapolate the elution temperatureusing the elution heating rate of 3° C./min. Reported elution peaktemperatures are obtained such that the observed comonomer contentcalibration curve agrees with those in U.S. Pat. No. 8,372,931.

The weight percentage of purge fraction (PF; Wt1), low density copolymercomponent (Wt2), high density copolymer component (Wt3), and highdensity fraction (HDF; Wt4) are defined as polymer peaks in thefollowing 4 temperature ranges: 25° to 33° C., 33° to 68° C., 68° to 92°C., and 92° to 115° C., respectively. Weight average molecular weightsof these four purge fractions are Mw1, Mw2, Mw3, and Mw4, respectively.The contribution of copolymer in the low density range of the overallpolymer by the molecular catalyst was reflected in the increased valueof Wt2/Wt3, the relative ratio of the amount of the low densitycopolymer to the higher density of copolymer in the overall polymerobtained. In some aspects the ratio Wt2/Wt3 is from 0.18 to 0.9,alternatively 0.19 to 0.81.

Catalyst efficiency (“Cat. Eff.”): calculate Cat. Eff. based on theamount of ethylene consumed during polymerization per gram of Ti in themagnesium halide-supported titanium catalyst (g ethylene/g Ti).

Batch reactor. A stirred 1-gallon reactor having a bottom valve.

Batch Reactor Copolymerization Test Method. Charge batch reactor with250 g of 1-octene and 1330 g of Isopar E. Heat reactor contents to 190°C., then saturate contents with ethylene in presence of 40 millimoles(mmol) of H₂. Mix suspension of catalyst (e.g., (B1) or (B2)) in liquid(e.g., (C1)) and activator (e.g., (A1)) in separate flask, andimmediately add resulting mixture into the batch reactor. Maintainpressure in the reactor at 3100 kilopascals (kPa; equal to 450 poundsper square inch (psi)) with ethylene flow to compensate for pressuredrop due to ethylene consumption during polymerization thereof. After 10minutes reaction time, open bottom valve and transfer reactor contentsinto a glass kettle. Pour contents of kettle onto a Mylar lined tray,allow contents to cool, and place tray in fume hood overnight toevaporate most of the liquid. Dry remaining resin in a vacuum oven togive a product poly(ethylene-co-1-octene) copolymer.

Hydrocarbylaluminoxane (A1). Modified methylaluminoxane, type 3A(MMAO-3A) having an approximate molecular formula[(CH₃)_(0.7)(isoC₄H₉)_(0.3)AlO. CAS No. 146905-79-5. Obtained as asolution in heptane from AkzoNobel N.V.

Compound (C1). Isopar E fluid. >99.75% to 99.9% of naphtha (petroleum),light alkylate, CAS 64741-66-8, and 0.1 to <0.25% isooctane CAS540-54-1, (isoalkanes mixture) obtained from Exxon Mobil Corporation.Having boiling range 114° to 139° C.

Particulate MgCl₂ (D1). Solid particulate MgCl₂ having a BET surfacearea of 375 to 425 m²/g. Product prepared by diluting a 20 wt % solutionof (F1), described below, in heptane into a measured quantity of (C1) togive a diluted solution; adding hydrogen chloride (HCl) slowly to thediluted solution with agitation at 30° C. until the molar ratio of Cl toMg reaches 2.04:1.00 while maintaining the temperature at 30°±3° C., togive a 0.20 M suspension of (D1) in (C1).

Titanium tetrachloride (E1). TiCl₄ obtained from Sigma Aldrich Company

Dialkylmagnesium (F1). Butyl-ethyl-magnesium. Used as a 20 wt % solutionin heptane.

Organoborate (G1). Methyldi((C₁₄-C₁₈)alkyl)ammonium salt oftetrakis(pentafluorophenyl)borate, prepared as described earlier. Amixture in a cycloalkane.

Trialkylaluminum (I1): triethylaluminum (TEA). (CH₃CH₂)₃Al solution inheptane.

Molecular Ligand-Metal Complex Procatalyst 1:bis((2-oxoyl-3-(3,5-bis-(1,1-dimethylethyl)phenyl)-5-(methyl)phenyl)-(5-2-methyl)propane-2-yl)2-phenoxy)-1,3-propanediylzirconium (IV)dimethyl, as disclosed in WO 2007/136494. Used as amixture in a cycloalkane.

For the following preparations, Ti loading, molar ratio of activator(e.g., TEA) or activator (e.g., (G1)) to titanium (“activator/Ti”),process conditions and data are listed later Table 1.

Preparation 1 (P1): Magnesium chloride-supported titanium procatalyst(B1). Add 0.80 milliliter (mL) of a 0.25 Molar (M) solution of (E1) in(C1) to 40 mL of a 0.20 M suspension of (D1) in (C1), and stir theresulting mixture overnight to give (B1) suspended in (C1).

Preparation 2 (P2): Magnesium chloride-supported titanium procatalyst(B2). Add 2.40 mL of a 0.25 M solution of (E1) in (C1) to 40 mL of a0.20 M suspension of (D1) in (C1), and stir the resulting mixtureovernight to give (B2) suspended in (C1).

Preparation 3A (P3A): enhanced Ziegler-Natta catalyst. Add 0.40 mL of a0.125 M solution of (A1) MMAO-3A in heptane to a suspension of P1 togive enhanced Ziegler-Natta catalyst of P3 suspended in (C1).

Preparation 3B (P3B): enhanced Ziegler-Natta catalyst. Add 0.24 mL of a0.125 M solution of (A1) MMAO-3A in heptane and 0.24 mL of a 0.003 Msolution of (G1) in methylcyclohexane to a suspension of P1 to giveenhanced Ziegler-Natta catalyst of P3B suspended in (C1).

Preparation 3C (P3C): enhanced Ziegler-Natta catalyst. Add 0.50 mL of a0.125 M solution of (A1) MMAO-3A in heptane to a suspension of P1 togive enhanced Ziegler-Natta catalyst of P3 suspended in (C1).

Preparation 3D (P3D): enhanced Ziegler-Natta catalyst. Add 0.98 mL of a0.125 M solution of (A1) MMAO-3A in heptane to a suspension of P1 togive enhanced Ziegler-Natta catalyst of P3 suspended in (C1).

Preparation 4A (P4A): enhanced Ziegler-Natta catalyst. Add 0.57 mL of a0.125 M solution of (A1) MMAO-3A in heptane to a suspension of P2 togive enhanced Ziegler-Natta catalyst of P4A suspended in (C1).

Preparation 4B (P4B) (prophetic): enhanced Ziegler-Natta catalyst.Replicate the procedure of P3B except use a suspension of P2 instead ofthe suspension of P1 to give enhanced Ziegler-Natta catalyst of P4Bsuspended in (C1).

Preparation 4C (P4C): enhanced Ziegler-Natta catalyst. Add 1.42 mL of a0.125 M solution of (A1) MMAO-3A in heptane to a suspension of P2 togive enhanced Ziegler-Natta catalyst of P4C suspended in (C1).

Preparation 4D (P4D): enhanced Ziegler-Natta catalyst. Add 0.20 mL of a1.77 M solution of (A1) MMAO-3A in heptane to a suspension of P2 to giveenhanced Ziegler-Natta catalyst of P4D suspended in (C1).

Preparation 5 (P5): magnesium halide-supported titanium procatalyst.Added 2.40 mL of a 1.0 M solution of EADC in (C1) to 40 mL of a stirredsuspension of 0.20 M MgCl₂ (D1) in (C1). Stirred resulting mixtureovernight at room temperature. Added 2.40 mL of a 0.25 M solution oftitanium tetraisopropoxide in (C1). Stirred resulting mixture overnightto give the magnesium halide-supported titanium procatalyst of P5suspended in (C1).

Preparation 6 (P6). Diluted suspension of procatalyst P5 to aconcentration of 0.0050 M to give suspension of magnesiumhalide-supported titanium procatalyst of P6 in (C1).

Preparation 7 (P7): Prepared a 0.0050 M solution of MolecularLigand-Metal Complex Procatalyst 1 in (C1).

Preparation 8 (P8). Molecular Ligand-Metal Catalyst 1 in (C1). Added asolution of (G1) in methylcyclohexane to the solution of procatalyst P7in a relative amount such that the molar ratio of (G1) to Zr metal ofMolecular Ligand-Metal Complex Procatalyst 1 was 2.4. Stirred for 5minutes to give Molecular Ligand-Metal Catalyst 1 in (C1) of P8.

Inventive Example A (IEA): Modified Ziegler-Natta Procatalyst 1 (MZN1):Added suspension of procatalyst P6 in (C1) to Molecular Ligand-MetalCatalyst 1 of P8 in (C1) to give Modified Ziegler-Natta Procatalyst 1 in(C1).

Inventive Example B (IEB): Modified Ziegler-Natta Procatalyst 2 (MZN2):Added suspension of procatalyst P5 in (C1) to solution of Procatalyst 1of P7 to give Modified Ziegler-Natta Procatalyst 2 in (C1).

Inventive Example Al (IEA1): preparation of Modified catalyst system 1(MCS1). Added activator (11) to Modified Ziegler-Natta Procatalyst 1 ofIEA to give Modified catalyst system 1 of IEA1 in (C1).

Inventive Example A2 (IEA2): preparation of Modified catalyst system 2(MCS2). Added activator (A1) to Modified Ziegler-Natta Procatalyst 1 ofIEA in (C1) to give Modified catalyst system 2 of IEA2 in (C1).

Inventive Example A3 (IEA3): preparation of Modified catalyst system 3(MCS3). Added activator (I1) (2 times as much as added in IEA1) toModified Ziegler-Natta Procatalyst 1 of IEA to give Modified catalystsystem 3 of IEA3 in (C1).

Inventive Example A4 (IEA4): preparation of Modified catalyst system 4(MCS4). Added activator (A1) (2 times as much as added in IEA2) toModified Ziegler-Natta Procatalyst 1 of IEA to give Modified catalystsystem 4 of IEA4 in (C1).

Inventive Example B1 (IEB1): preparation of Modified catalyst system 5(MCSS). Added activators (I1) and (G1) to Modified Ziegler-NattaProcatalyst 2 of IEB to give Modified catalyst system 5 of IEB1 in (C1).

Inventive Example B2 (IEB2): preparation of Modified catalyst system 6(MCS6). Added activators (A1) and (G1) to Modified Ziegler-NattaProcatalyst 2 of IEB to give Modified catalyst system 6 of IEB2 in (C1).

Inventive Example B3 (IEB3): preparation of Modified catalyst system 7(MCS7). Added activators (I1) (2 times as much as added in IEB1) and(G1) to Modified Ziegler-Natta Procatalyst 2 of IEB to give Modifiedcatalyst system 7 of IEB3 in (C1).

Inventive Example B4 (IEB4): preparation of Modified catalyst system 8(MCS8). Added activators (A1) (2 times as much as added in IEB2) and(G1) to Modified Ziegler-Natta Procatalyst 2 of IEB to give Modifiedcatalyst system 8 of IEB4 in (C1).

Comparative Example 1 (CE1): Added activator (I1) to Procatalyst P6 togive a comparative Ziegler-Natta catalyst.

Comparative Example 2 (CE2): Added activators (G1) and (A1) toProcatalyst P6 to give a comparative Ziegler-Natta catalyst.

Comparative Example 3 (CE3): Added activators (I1) and (G1) toProcatalyst P7 to give a comparative Ziegler-Natta catalyst.

Comparative Example 4 (CE4): Added activators (G1) and (A1) toProcatalyst P7 to give a comparative Ziegler-Natta catalyst.

Inventive Examples Polymerizations with different modified catalystsystems of IEA1 to IEA4 and IEB1 to IEB4 and different unmodifiedcatalysts of CE1 to CE4. In separate runs, replicate the Batch ReactorCopolymerization Test Method as follows. Charge batch reactor with 250 gof 1-octene and 1330 g of Isopar E. Heat reactor contents to 190° C.,then saturate contents with ethylene in presence of 40 millimoles (mmol)of molecular hydrogen. For different runs add different ones of Modifiedcatalyst systems 1 to 8 (MCS1 to MCS8) of IEA1 to IEA4 and IEB1 to IEB4and catalysts CE1 to CE4, respectively, into the batch reactor. Maintainpressure in the reactor at 3100 kPa with ethylene flow to compensate forpressure drop due to ethylene consumption during polymerization thereof.After 10 minutes reaction time, open bottom valve and transfer reactorcontents into a glass kettle. Pour contents of kettle onto a Mylar linedtray, allow contents to cool, and place tray in fume hood overnight toevaporate most of the liquid. Dry remaining resin in a vacuum oven togive a product poly(ethylene-co-1-octene) copolymer from polymerizationswith IEA1 to IEA4, IEB1 to IEB4 and CE1 to CE4, respectively.

Modified catalyst system compositions and polymerizationcharacterization data are reported below in Table 1 and later in Table2, respectively.

TABLE 1 Modified catalyst system Compositions. Procatalyst loading Ti +Molar ratio Zr.+ G (μmol + μmol + TEA/(Ti + Molar ratio Molar ratio Ex.No. MCS μmol) Zr) (G1)/(Ti + Zr) (A1)/(Ti + Zr) IEA1 MCS1 3 + 3 + 7.2 50 0 IEA2 MCS2 3 + 3 + 7.2 0 0 25 IEA3 MCS3 3 + 3 + 7.2 10 0 0 IEA4 MCS43 + 3 + 7.2 0 0 50 IEB1 MCS5 3 + 3 + 0 5 0.6 0 IEB2 MCS6 3 + 3 + 0 0 0.625 IEB3 MCS7 3 + 3 + 0 10 1.2 0 IEB4 MCS8 3 + 3 + 0 0 1.2 50 CE1 P6 3 +0 + 0 10 0 0 CE2 P6 3 + 0 + 0 0 1.2 50 CE3 P7 0 + 2 + 0 10 1.2 0 CE4 P70 + 2 + 0 0 1.2 50

The modified catalyst systems 1 to 8 of IEA1 to IEA4 and IEB1 to IEB4,respectively, and comparative procatalysts 1 to 4 of CE1 to CE4,respectively, that were used in the solution phase polymerizationprocesses had efficiencies and produced polyolefins having CEFcomposition analysis results shown below in Table 2. The contribution ofcopolymer in the low density range of the overall polymer by themolecular catalyst was reflected in the increased value of Wt2/Wt3, therelative ratio of the amount of the low density copolymer to the higherdensity of copolymer in the overall polymer obtained.

TABLE 2 Catalyst Performance and Polyolefin Characterization Data. Cat.Ex. No. Cat. Eff. Wt2/Wt3 IEA1 154300 0.19 IEA2 149400 0.38 IEA3 1285000.46 IEA4 110700 0.79 IEB1 171700 0.24 IEB2 163000 0.80 IEB3 167400 0.81IEB4 133800 1.55 CE1 371900 0.14 CE2 382800 0.15 CE3 178000 8.01 CE4180200 7.95

As shown in Table 2, the modified Ziegler-Natta procatalyst, made bymodifying an initial Ziegler-Natta procatalyst and a molecular(pro)catalyst and an organoborate activator (G1), used to prepare themodified catalyst systems 1 and 3 of IEA1 and IEA3, respectively, wassuccessfully activated in the preparations with a trialkylaluminum, andthe resulting modified catalyst systems 1 and 3 were used successfully,as if a single catalyst component, in a polymerization reaction thatproduced a polyolefin composition of polyolefin macromolecules of twodistinct types: first polyolefins made by Ziegler-Natta catalysts andsecond polyolefins made by molecular catalysts. The modifiedZiegler-Natta procatalyst was also used, as if a single procatalystcomponent, in a polymerization reaction with (A) hydrocarbylaluminoxaneas activator that produced a mixture of polyolefin composition of thetwo distinct types of polyolefin macromolecules (e.g., made withmodified catalyst systems IEA2 and IEA4). Another modified Ziegler-Nattaprocatalyst, made by modifying an initial Ziegler-Natta procatalyst anda molecular (pro)catalyst, used to prepare the modified catalyst systems6 and 8 of IEB2 and IEB4, was successfully activated in the preparationswith a combination of (A1) and (G1) activators that also produced amixture of polyolefins of the two distinct types of macromolecules. Thesame modified Ziegler-Natta procatalyst was also used, as if a singleprocatalyst component, in a polymerization reaction with a combinationof (I1) and (G1) activators as activator that produced a mixture ofpolyolefin composition of the two distinct types of polyolefinmacromolecules (e.g., made with modified catalyst systems IEB5 andIEB7). Comparison of IEA1 and IEA3 or IEA2 and IEA4 indicated thathigher amount of activator, e.g., (A1) or (I1), increased the amount ofpolyolefins made with the molecular catalyst in the product polyolefincomposition. Similarly, an increase of the amount of polyolefinmacromolecules made with the molecular catalyst in the productpolyolefin composition was also achieved by increasing the amount ofactivators, e.g., (I1) and (G1) for IEB1 versus IEB3, and activators(A1) and (G1) for IEB2 and IEB4. The foregoing benefits may characterizeembodiments of the inventive method and polyolefins described earlierand claimed below.

1.-15. (canceled)
 16. A modified Ziegler-Natta procatalyst that is prepared by mixing an initial Ziegler-Natta procatalyst and a molecular (pro)catalyst together in (C) a saturated or aromatic hydrocarbon liquid under modifying conditions comprising a modifying temperature less than 100° C. and a modifying time of at least 1 minute, and optionally an activator, to give the modified Ziegler-Natta procatalyst; wherein the modified Ziegler-Natta procatalyst is free of a trialkylaluminum; and wherein the activator is selected from the group consisting of: (i) a (A) hydrocarbylaluminoxane; (ii) an organoborate or an organoboron; and (iii) both (i) and (ii).
 17. The modified Ziegler-Natta procatalyst of claim 16 wherein the activator is present and is selected from the group consisting of: (i) the (A) hydrocarbylaluminoxane or (iii) both (i) the (A) hydrocarbylaluminoxane and (ii) the organoborate or organoboron.
 18. The modified Ziegler-Natta procatalyst of claim 16: (i) wherein the initial Ziegler-Natta procatalyst is (B) a magnesium halide-supported titanium procatalyst; wherein the (B) magnesium halide-supported titanium procatalyst has been prepared by contacting (D) a solid particulate consisting essentially of magnesium halide with (E) titanium tetrachloride in the (C) saturated or aromatic hydrocarbon liquid so as to give the (B) magnesium halide-supported titanium procatalyst; (ii) wherein the molecular (pro)catalyst consists essentially of a molecular ligand-metal complex (pro)catalyst; or (iii) both (i) and (ii).
 19. The modified Ziegler-Natta procatalyst of claim 16 wherein the modifying conditions comprise: (i) a modifying temperature from 0° C. to 50° C.; (ii) a modifying time from 3 hours to 3 months; (iii) an inert gas atmosphere (e.g., molecular nitrogen, helium, argon, or a mixture of any two or more thereof); (iv) both (i) and (ii); (v) both (i) and (iii); (vi) both (ii) and (iii); or (vii) each of (i), (ii), and (iii).
 20. The modified Ziegler-Natta procatalyst of claim 16 wherein: (i) the initial magnesium halide-supported titanium procatalyst is free of Al (molar ratio of Al/Mg=0); (ii) the initial magnesium halide-supported titanium procatalyst has a molar ratio of Al/Mg from >0 to <0.05; (iii) the magnesium halide of the initial magnesium halide-supported titanium procatalyst is magnesium chloride; (iv) the magnesium halide of the initial magnesium halide-supported titanium procatalyst is magnesium bromide; (v) both (i) and (iii); (vi) both (i) and (iv); (vii) both (ii) and (iii); (viii) both (ii) and (iv).
 21. The modified Ziegler-Natta procatalyst of claim 16 wherein: (i) the (D) solid particulate consisting essentially of magnesium halide has a Brunauer, Emmett, Teller (BET) surface area of >200 square meters per gram (m²/g) as measured by Brunauer, Emmett, Teller (BET) Surface Area Method; or (ii) the (D) solid particulate consisting essentially of magnesium halide has been prepared by contacting a solution of (F) a dialkylmagnesium compound dissolved in the (C) saturated or aromatic hydrocarbon liquid with 1.95 to 2.05 mole equivalents of hydrogen halide to give a suspension of the (D) solid particulate consisting essentially of magnesium halide in the (C) saturated or aromatic hydrocarbon liquid; or (iii) both (i) and (ii).
 22. The modified Ziegler-Natta procatalyst of claim 16 wherein the activator used with the modified Ziegler-Natta procatalyst comprises the (A) hydrocarbylaluminoxane.
 23. The modified Ziegler-Natta procatalyst of claim 16 wherein the molecular ligand-metal (pro)catalyst comprises: (i) a cyclopentadienyl ligand-metal complex (pro)catalyst; (ii) a cyclopentadienyl-free ligand-metal complex (pro)catalyst; or (iii) both (i) and (ii).
 24. A modified catalyst system comprising a product of a reaction of the modified Ziegler-Natta procatalyst of claim 16 with an activator.
 25. The modified catalyst system of claim 24 further comprising (G) an organoborate or (H) an organoboron. 